Effect of heating and cooling atmospheres on colors of glaze and glass containing copper

ESR and ESCA analyses of a copper red glaze prepared by firing under a strongly reducing atmosphere followed by oxidation during a cooling period showed that Cu¹⁺ and Cu₂O were major species in it. From the investigation of behavior and chemical states of copper and tin under various firing conditions, mechanisms of the formation of Cu₂O and its protection were assumed as follows: Cu²⁺ and Sn⁴⁺ are reduced to metals during reducing firing and then the metals aggregate in the glaze surface layer, forming alloy. In the next oxidation process, metallic copper and tin are oxidized to Cu₂O or Cu¹⁺ and SnO respectively. Due to the affinity of SnO on Cu₂O for glass, glass containing Sn²⁺ surrounds and consequently protects Cu₂O from excessive oxidation.

A colorless copper glass before striking contained copper mainly as Cu¹⁺. ESCA analysis showed that striking of the glass caused the selective formation of Cu₂O.     

Positron annihilation lineshape studies as a supplement method to lifetime measurement

We studied positron annihilation lineshapes by a Ge(Li) γ-ray spectrometer for CCl₄ solution in benzene and two monomer crystals which are polymerized by γ-ray irridation. From the lineshapes we evaluated the para-positronium intensity, and the results agree well with those of lifetime measurements in the cases of CCl₄ solutions in benzene and solid acrylamide. But in solid dimethylitaconate the results from the two different methods have not agreed.     

Frequency-Domain Measurements of Diffusing Photon Propagation in Solid Phantoms

Photon propagation in a highly scattering medium such as living tissue is well described by the photon diffusion equation. In a homogeneous and isotropic case, the equation has analytically been solved for a medium with a simple geometrical shape. We report frequency-domain measurements using slab-shaped solid phantoms. Comparison of the results with computer simulations proves the validity of extrapolated boundary conditions.     

Low-temperature 15N NMR spectra of reduced 1,3-heterocyclic systems

The ¹⁵N NMR spectra of the O-inside cis-fused conformer of perhydropyrido[1,2-c][1,3]thiazine shows a shielding of the nitrogen of 23.0 ppm relative to the trans-fused conformer. In contrast, ¹⁵N shifts for the cis-and trans-fused conformers of perhydro-oxazolo[3,4-a]pyridine and perhydrothiazolo[3,4-a]pyridine show corresponding shieldings of only 0.6 and 2.5 ppm, respectively.     

Modification of α-santonin VI. Synthesis of (+)-deoxyvernolepin

(+)-Deoxyvernolepin is synthesized from α-santonin via angular methyl activation and subsequent furan ring opening.     

Preparation of macroreticular-type oleophilic anion exchange resin membrane and its permselectivity to halides and thiocyanate

Macroreticular-type oleophilic anion exchange resin membranes containing high-molecular-weight ammonium ions such as tri-n-octylbenzylammonium and tri-n-dodecylbenzylammonium as fixed site were freshly prepared. These membranes were wetted well with water-immiscible organic solvents even in aqueous surroundings. The properties of the membrane, i.e. porosity, water and organic solvent content, capacity and conductivity were determined. The permselectivity of the membrane impregnated with nitrobenzene or o-nitrophenyloctylether to halide and thiocyanate ions was evaluated by measurement of bi-ionic membrane potential and electrodialysis. p]The sequence of the permselectivity was Cl^? < Br^? < I^? < SCN^?, and was consistent with the Hofmeister anion series. The value of the permselectivity was 10–100 times larger than that of usual hydrophilic anion exchange membranes. It was found that the permselectivity of the present membrane was strongly dependent on the separation factor, which was in turn affected by the hydrophobicity of the membrane. The effect of the ion association between fixed ion-exchange site and counter ion on the specific conductance of the membrane was also discussed.     

A mobile computerized laser radar system for observing rapidly varying meteorological phenomena

A high repetition, mobile laser radar system with a computerized real-time data acquisition and display system is described. Signal-to-noise levels of the system are compared with theoretical values, and it is found that they are affected by the shot noise in the system. An example of a stack plume observation is also presented to show the performance of the system.